In the anime

Samurai appeared in the episode Challenge of the Samurai. Ash and Misty were traveling through Viridian Forest, and Ash intended to catch more Pokémon. He was just about to catch a Weedle when Samurai jumped out of the bushes and threatened him with his sword, demanding to know if Ash was from Pallet Town. Samurai challenged Ash to a battle, having already lost to Gary and the other two Trainers from Pallet.

In the confusion caused by Samurai's yelling and sword-waving, the Weedle escaped. Samurai insulted Ash, saying that he is a "bad Trainer". Because of this, they started a battle. Samurai's powerful Pinsir knocked out Ash's Pidgeotto, but Ash's Metapod used Harden to damage Pinsir's pincers. Samurai sent out his own Metapod, and the two Pokémon, being unable of using any move besides Harden, were locked in a complete stalemate for hours.

Their match was interrupted by a Beedrill swarm, apparently angered by Ash's attack of the Weedle earlier. The Beedrill snatched Ash's Metapod and flew off. The trio hid in Samurai's cabin, where the boy continued to berate and insult Ash, saying that Ash was not a good Trainer to his Pokémon because he didn't go to rescue his Metapod when the Beedrill attacked.

Samurai eventually gained respect for Ash when he used his newly evolved Butterfree to put the Beedrill to sleep by using Sleep Powder and reunited with his Pokémon.

At the end of the episode, Ash, Misty, and Samurai say good-bye, and the two boys say that they will battle again some day.

He made a cameo appearance with his Pinsir in the second opening theme, The Rivals, and its English dub counterpart, Pokémon World.

Pokémon

This listing is of Samurai's known Pokémon:

Pinsir

Pinsir was the first Pokémon Samurai used in his match against Ash. It was able to defeat Pidgeotto easily with a Tackle (though Pidgeotto was already weakened from its battle directly before with a wild Weedle), but when it tried to break Ash's Metapod in half with its pincers, Metapod used Harden and the attack backfired.

After Pinsir's failure against Ash's Metapod, Samurai sent out his own Metapod. Since neither Pokémon could use any move other than Harden, both Trainers ordered their Pokémon to harden again and again for several hours, until they had to stop their battle.

Through flashback, it is known that Samurai also used Metapod to battle Gary's Squirtle, and lost.